Compressor construction

ABSTRACT

A hermetic compressor comprising compression mechanism and a motor for driving the piston means within the compression mechanism, with the motor being supported directly in the outer housing of the compressor by mounting means including a laminate formed integrally with the stator of the drive motor.

United States Patent [191 Parker July 29, 1975 1 1 COMPRESSORCONSTRUCTION [75] Inventor: Sidney A. Parker, Fort Worth, Tex.

[73] Assignee: Lennox Industries Inc.,

Marshallto'wn, Iowa [22] Filed: Oct. 29, 1973 [21] App1.No.: 410,821

Related U.S. Application Data [63] Continuation of Ser. No. 223,437,Feb. 4, 1972,

abandoned.

[52] U.S. C1. 417/363 [51] Int. Cl. F04b 17/00 [58] Field of Search417/419, 363, 902

[56] References Cited UNITED STATES PATENTS 1,446,898 2/1923 Gysel310/58 1,948,846 2/1934 Des R0ches.. 417/363 1,998,604 4/1935 Be1den417/902 2,287,203 6/1942 Smith 417/902 3,015,222 1/1962 We11born 417/9023,065,901 11/1962 Neubauer 417/363 3,074,347 1/1963 Clymer 417/3633,356,293 12/1967 Butts 417/902 3,448,918 6/1969 Cawley 417/3633,462,075 8/1969 Dirk et a1 417/419 FOREIGN PATENTS OR APPLICATIONS1,007,418 5/1951 Germany 310/89 1,046,075 12/1958 Germany 417/4101,137,797 10/1962 Germany 310/258 Primary ExaminerWi11iam L. FreehAttorney, Agent, or FirmMo1inare, A11egretti, Newitt & Witcoff ABSTRACTA hermetic compressor comprising compression mechanism and a motor fordriving the piston means within the compression mechanism, with themotor being supported directly in the outer housing of the compressor bymounting means including a laminate formed integrally with the stator ofthe drive motor.

7 Claims, 14 Drawing Figures PATENIEDJULZQ ms FIG. 76

FIG. 7b

FIGS

PATENTEDJULZQIQYS 3.. 897. 177 sum 3 FIG. [0 2m COMPRESSOR CONSTRUCTIONRELATED APPLICATION This is a continuation, of application Serial No.

223,437 filed Feb. 4, 1972 now abandoned. BACK- GROUND OF THE INVENTIONThis invention relates to a hermetic compressor for use in refrigerationsystems or air-conditioning applications having an improved electricdrive motor construction incorporating integrally formed mounting meansfor the compression mechanism and motor.

In the past, hermetic compressors have been made with a compressionmechanism comprising a crankcase portion with cylinders therein and anannular portion for receiving and housing therein the electric drivemotor for the drive shaft for moving pistons within the cylinders. Theannular portion is a part of the compression mechanism casting. Suchconstruction is relatively bulky and expensive and a number of differentattempts have been made in order to reduce the weight of the compressionmechanism casting and to reduce cost of manufacture of such compressor.

An object of the present invention is to provide an improved hermeticcompressor having an electric drive motor wherein the stator isconstructed and arranged so as to materially reduce the size and cost ofthe compression mechanism casting and thus reduce the overall cost ofthe compressor.

Another object of the present invention is to provide an improvedhermetic compressor with a stator having mounting means integrallyformed thereon so as to mount the stator within the outer casing of thehermetic compressor.

Yet another object of the present invention is to provide an improvedhermetic compressor which includes an electric drive motor having astator formed from laminates bonded to one another, with at least one ofthe laminates constructed and arranged so as to provide mounting meansto support the stator in the outer casing, together with the compressionmechanism secured thereto. Other objects and advantages of the presentinvention will become more apparent hereafter.

BRIEF DESCRIPTION OF THE DRAWING There is shown in the attached drawinga presently preferred embodiment of the present invention wherein likenumerals refer to like elements in the various views and wherein:

FIG. 1 is an elevation view of an improved compressor embodying thepresent invention, with parts broken away to better show the internalconstruction;

FIG. 2 is an end view of the improved compressor of FIG. 1, with partsbroken away;

FIG. 3 is a plan view of the improved compressor of FIG. 1, with partsbroken away;

FIG. 4 is an elevation cross-sectional view of the compression mechanismcasting of the present invention;

FIG. 5 is a plan view of the compression mechanism casting;

FIG. 6 is an end view of the compression mechanism casting;

FIG. 7 is a cross sectional view of the improved stator of the electricdrive motor of the present invention;

FIG. 7a is an enlarged detail view of a portion of the improved electricdrive motor illustrating a mounting means laminate structure having aninside radius substantially equal to that of the laminates comprisingthe stator;

FIG. 7b is an enlarged detail view of a portion of a modified electricdrive motor illustrating a mounting means laminate structure cut-away atthe inside radius to provide for improved electric characteristics;

FIG. 8 is a plan view of the improved stator of the electric drive motorof FIG. 7;

FIG. 9 is an elevation view of a modified compressor, with parts brokenaway;

FIG. 10 is an end view of the modified compressor of FIG. 9, with partsbroken away;

FIG. 11 is a plan view of the stator of the electric drive motoremployed in the compressor of FIG. 9; and

FIG. 12 is a cross sectional view of the stator of FIG. 11.

DETAILED DESCRIPTION OF THE PRESENT INVENTION Referring to FIGS. 1, 2and 3, there is illustrated a hermetic compressor embodying the presentinvention. The compressor 10 comprises a gas-tight outer housingincluding an upper shell 12 and a lower shell 13, integrally joined toone another as, for example, by weldmg.

If desired, a plurality of legs (not shown) may be secured to the bottomof the exterior surface of the lower shell 13 so as to support thecompressor in an upright position within a condensing unit or anair-conditioning unit.

Resiliently supported within the outer housing or casing of thecompressor 10 is a compression mechanism 16 which includes the novelelectric motor of the present invention. The compression mechanismincludes a compressor block or body 18 having a base portion 19 and acrankcase portion with cylinders 20 defined therein for receivingpistons 22. The pistons 22 are adapted to be reciprocated within thecylinders 20 by means of a drive shaft 24 journalled within thecompressor body or block 18. Connecting rods 26 operatively connect thepistons 22 to the drive shaft.

Provided at the end of each cylinder 20 is a discharge and suction valveassembly 28. Each discharge and suction valve assembly 28 is comprisedof a discharge valve unit and a suction valve unit operative in a knownmanner to control the flow of refrigerant gas to and from the cylinders20. Head means 29 enclose the end of each cylinder 20.

The lower end of drive shaft 24 is journalled in lower hub plate 39 thatis secured to the body or block 18 by suitable means, for example, bolts41. Thrust washer 43 held in place by plate 45 takes up the drive shaftthrust.

It will be understood that the returning suction gas from the suctionline of a refrigeration system will enter the outer casing of thecompressor 10 and pass upwardly over the electric drive motor 34 whichincludes a stator 36 and a rotor 38, into suction shroud 33 and throughthe conduits 30 and 32 into the cylinders 20, wherein the gas iscompressed and then discharged through the discharge and suction valveassemblies 28 into the head area 40 of each cylinder. From the headarea, the gas passes into the discharge mufflers 42 and then intodischarge line 44 for communication to the discharge line of therefrigeration system.

During operation, rotation of the drive shaft 24 will cause oil in thesump formed in the bottom of the lower shell 13 to be ingested into theopening in the drive shaft 24 and forwarded to the various shaft journalsurfaces and connecting rod bearing surfaces that require lubrication.

An important feature of the present invention is the construction of thestator of the electric drive motor 34 wherein a portion of the statorserves as the main support with the outer casing for the compressionmechanism 16 and motor 34. This construction results in a materiallyreduced weight of the compressor as the annular motor support portion ofprior castings can be obviated by the present design. Essentially, inthe present design a laminate 36b of the stator 36 functions as aportion of the support for the motor 34 and compressor block 16. Thelaminate 36b includes mounting means which cooperate with resilientspring means 46 to mount the compression mechanism resiliently withinthe outer housing of the compressor 10. Elongated bolts 55 extendthrough openings 57 in the stator 36 for connecting the stator to thetapped holes 56b in the mounting projections 56 on compressor block 18.

The resilient means 46 include a coil spring 62 disposed between abracket 63 secured to the lower shell 13 of the outer casing and an earof the laminate 36b of motor 34. Bolt 64 extends through each opening 60in the laminate 36b and is secured to bracket 63 so as to maintain theparts in assembled relationship.

With reference to FIGS. 4, 5, 6 and 8, there is illustrated acompression mechanism casting of the present invention. The compressionmechanism block or body 18 includes a base portion 19 from which thecylinders 20 depend. In the illustrated embodiment of the presentinvention, a two-cylinder casting is shown.

Extending upwardly and downwardly from the central portion of the base19 is a journal hub 50 having bearing liners 52 positioned therein forjournalling the drive shaft 24. The mounting projections 56 extendupwardly from the base portion 19, and as best seen in FIG. 5, there arefour projections 56 extending up wardly from the compressor block in theembodiment illustrated. Dowel pins (not shown) extend from openings 560into openings 37 in the stator in order to properly align the motor 34on the compressor block casting l8.

Openings 58 and 59 corporate with suction conduits and 32 to admitsuction into suction gas into cylinder 20.

Considering now FIGS. 7, 7a and 8, there is illustrated an electricdrive motor 34 embodying principles of the present invention. The motor34 is comprised of a stator 36 and a rotor 38 (not shown) adapted to berotatably mounted within the stator and inductively coupled thereto. Thestator 36 of motor 34 is comprised of laminates or layers 36a of sheetmetal or like magnetic properties, which were heretofore welded to oneanother and which are presently often secured by epoxy bonding, with endwindings secured to the stator laminates to complete the winding for thestator. The laminates 36a are epoxy bonded or similarly joined to oneanother so as to minimize any power losses resulting from the weldingprocess heretofore employed and to eliminate motor laminate noise.

A feature of the present invention is the use of a thicker laminate 36bforming a part of the laminated stack of stampings. The laminate 36bprovides a part of the mounting means for the electric drive motor 34and compressor block 18 within the outer casing. As

shown, the laminate 32b is provided with holes in the corners thereofwhich are adapted to cooperate with the resilient means 46 to supportthe motor 34 and compression mechanism 16 secured thereto within theouter casing of the compressor 10.

Turning to FIG. 71), there is illustrated a modified form of electricdrive motor 134 incorporating a laminate 136 in the stator lamination136a. In this construction, the inner portion of the laminate 136i; iscut outwardly so as to have larger inside radius than the laminations136 of the stator. In some applications, this construction will provideless power losses than would result from the construction of FIG. 7a.

The material savings resulting from utilizing a compression mechanismincorporating an improved motor as shown by the present invention isevidenced by the following test information which indicates that acompressor embodying the improved motor and compression mechanismcasting is capable of producing 72,000 BTU/HR capacity at 45F evaporatorcoil and 125F condensing F return gas and zero sub-cooling as comparedwith a known comparable compressor which is capable of producing 58,000BTU/HR capacity at the same conditions. The casting of the presentinvention weighs one-half that of the casting of the compressor having58,000 btu capacity. Casting fabrication is materially simplified and inaddition, a substantial savings is effective in cost of materials.

With reference to FIGS. 9, 10, 11 and 12 there is illustrated a modifiedcompressor incorporating a new and novel mounting arrangement for thecompressor mechanism. The compressor 210 includes resilient mountingmeans 246 disposed in the compressor such that the mounting plane (theplane through laminate 236b) is above the center of gravity of thecompression mechanism 216. This arrangement provides for greatermounting stability of the compression mechanism 216 within the outercasing.

In general, the remaining components of compressor 210 are the same asthose in compressor 10 and accordingly like numerals have been appliedto like elements in the various views with the exception that thenumerals in FIGS. 9, 10, 11 and 12 are preceded by the numeral 2. Thusthe shell or outer casing portion is identified as 12 in FIG. 1 and 212in FIG. 9.

The new and novel mounting system for the compressor mechanism providesfor greater mounting stability of the compression mechanism by allowingthe mounting plane of the compression mechanism to be above orsubstantially the same as the center of gravity of the compressionmechanism. This improvement is not being used currently in refrigerantcompressors known to me.

There has been provided by the present invention an improved hermeticcompressor incorporating a novel electric drive motor having means formounting same directly on the body of the compression mechanism anddirectly to the interior of the outer casing of the compressor. Themounting means are readily fabricated as a part of the stator withoutmaterially adding to the cost thereof. In a preferred form of theinvention, the laminations of the stator are epoxy-bonded to one anotherwith the result that noise sometimes attendant to the welding oflaminations and the thermal cracking or shock occurring in weldedlaminates one to the other is obviated. As a result of use of thepresent invention, substantial savings result in fabrication of thehermetic compressor since the fabrication can be accomplished by thestep of resiliently supporting the stator of the drive motor directlyfrom the outer casing, while at the same time supporting the compressionmechanism on the electric drive motor and improving the stability of thecompressor mounting system.

While I have described a preferred embodiment of my invention, it willbe understood that my invention is not limited thereto since it may beotherwise embodied within the scope of the following claims.

I claim:

l. A hermeticcompressor comprising an outer housing, a body definingcylinder means, piston means disposed in said cylinder means, a driveshaft operatively connected to the piston means for moving same, a motorsecured to the drive shaft for rotating same, said motor including astator operatively affixed to the body and a rotor operatively connectedto the drive shaft, the motor incorporating resilient mounting means forsupporting same in the outer housing, said stator comprising a pluralityof laminates secured to one another, said mounting means comprising alaminate formed integral with said stator, the plane of said laminatebeing above or substantially the same as the center of gravity of thebody and aligning means for aligning the stator on the body disposedbetween the stator and the body.

2. A compressor as in claim 1 wherein bracket means are provided in thecompressor, and spring means are positioned between the bracket meansand the mounting means for resiliently supporting said body and motor inthe compressor.

3. A compressor as in claim 1 wherein the plane of said laminate isabove the center of gravity of the body.

4. A compressor as in claim 1 wherein the body comprises a base portionwith at least one cylinder means thereon.

5. A compressor as in claim 4 wherein projections extend from said baseportion for cooperatively engaging with said stator.

6. A compressor as in claim 4 wherein said aligning means comprise dowelmeans.

7. A hermetic compressor comprising an outer housing, a body definingcylinder means, piston means disposed in said cylinder means, a driveshaft operatively connected to the piston means for moving same, a motorsecured to the drive shaft for rotating same, said motor including astator operatively affixed to the body and a rotor operatively connectedto the drive shaft, the motor incorporating resilient mounting means fordirectly supporting same within the outer housing, said statorcomprising a plurality of laminates secured to one another, saidmounting means comprising a laminate formed integral with said stator,the plane of said laminate being above or substantially the same as thecenter of gravity of the body, said body requiring less material than acomparable body that has a portion encircling the stator and aligningmeans for aligning the stator on the body.

1. A hermetic compressor comprising an outer housing, a body definingcylinder means, piston means disposed in said cylinder means, a driveshaft operatively connected to the piston means for moving same, a motorsecured to the drive shaft for rotating same, said motor including astator operatively affixed to the body and a rotor operatively connectedto the drive shaft, the motor incorporating resilient mounting means forsupporting same in the outer housing, said stator comprising a pluralityof laminates secured to one another, said mounting means comprising alaminate formed integral with said stator, the plane of said laminatebeing above or substantially the same as the center of gravity of thebody and aligning means for aligning the stator on the body disposedbetween the stator and the body.
 2. A compressor as in claim 1 whereinbracket means are provided in the compressor, and spring means arepositioned between the bracket means and the mounting means forresiliently supporting said body and motor in the compressor.
 3. Acompressor as in claim 1 wherein the plane of said laminate is above thecenter of gravity of the body.
 4. A compressor as in claim 1 wherein thebody comprises a base portion with at least one cylinder means thereon.5. A compressor as in claim 4 wherein projections extend from said baseportion for cooperatively engaging with said stator.
 6. A compressor asin claim 4 wherein said aligning means comprise dowel means.
 7. Ahermetic compressor comprising an outer housing, a body definingcylinder means, piston means disposed in said cylinder means, a driveshaft operatively connected to the piston means for moving same, a motorsecured to the drive shaft for rotating same, said motor including astator operatively affixed to the body and a rotor operatively connectedto the drive shaft, the motor incorporating resilient mounting means fordirectly supporting same within the outer housing, said statorcomprising a plurality of laminates secured to one another, saidmounting means comprising a laminate formed integral with said stator,the plane of said laminate being above or substantially the same as thecenter of gravity of the body, said body requiring less material than acomparable body that has a portion encircling the stator and aligningmeans for aligning the stator on the body.